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South Fork Tolt River Near Index

South Fork Tolt River · Pacific NW · USGS gage 12147600

Coldwater (summer mean 12.7°C — prime coldwater).

Water
51°F
Flow
15 cfs
Air
76°F
Sky
100%
Predicted hatches · 2026-06-15
PredictedGreen DrakeDrunella spp.0.69
Predicted by conditions; no reports yet. water 10.8°C (51°F) is warming toward the prime band (11-15°C); peak season; 2 days sustained ≥10°C (wants 3); watch midday, often cloudy.
flies: Green Drake Parachute #10-12, Cripple, Hares Ear #10
PredictedMidgeChironomidae0.43
Predicted by conditions; no reports yet. water 10.8°C (51°F) is cooling past the prime band (1-10°C); shoulder of the season; 8 days sustained ≥0°C; watch midday, especially cold months.
flies: Zebra Midge #18-22, Griffith's Gnat, Disco Midge

PREDICTED from the first-principles model only. Report-confirmed signal (fly-shop & forum reports) is the next milestone.